Joint construction



Sept. 27, 1938. M, DE UN 2,131,553

JOINT CONSTRUCTION Filed July 21, 1957 E 11v VENTOk Mari?? 1761i ATTORNEY Patented Sept. 27, 1938 PATENT OFFICE JOINT CONSTRUCTION Martin De Lin, Holland, Mich., assignor to Holland Furnace Company, Holland, Mich, a cor poration of Michigan Application July 21, 1937, Serial No. 154,7011

1 Claim. (01. 285-25) This invention relates to joint constructions, and more particularly to a joint construction adapted to be utilized for securing a cast metal cylinder to a sheet metal cylinder. The invention finds especial use in connecting a sheet metal stove pipe to the cast metal flue outlet of a combustion chamber for furnaces.

In furnace constructions it is common practice toconnect sheet metal stove pipe to the cast metal outlet collar of the combustion chamber by fitting a crimped end of the sheet metal cylinder over the cast metal collar. Such joints are unsatisfactory because of the different coefficients of expansion of the two cylinders, and because a sudden increase in pressure within the combustion chamber may blow the sheet metal pipe loose from the cast metal collar. This disadvantage is not entirely overcome by bolting or otherwise securing the sheet metal pipe to the cast metal 001- lar, because relative movement occurs between the two parts and permits leakages around the joint.

The present invention accordingly has for its primary object the provision of a joint construction for cast metal and sheet metal cylinders which is not subject to the disadvantages mentioned above. This object is attained, in part, by forming the cast metal cylinder with a radial face at one end thereof, providing the sheet metal cylinder with a radial flange, and by encircling the sheet metal cylinder with a cast metal sleeve having a radial flange which is bolted directly to the radial face of the cast metal sleeve whereby the radial flange of the sheet metal cylinder is securely locked between the cast metal cylinder and the radial flange of the cast metal sleeve.

The joint thus formed is made leak proof by providing an annular groove in'the radial face of the cast metal member which is filled with compressible packing material. The radial flange of the sheet metal cylinder is pressed firmly against the packing material in the groove by the cast metal sleeve. The packing material thus effectively seals the joint between the two cylinders.

For a better understanding of the invention reference should now be had to the accompanying drawing, wherein Figure 1 is a perspective view of a furnace construction showing a sheet metal pipe secured to the cast metal collar of a combustion chamber in accordance with the present invention;

Figure 2 is a sectional view through the joint between the cast metal collar and the sheet metal pipe taken on substantially the line 2-2 of Figure 1; and

Figure 3 is an exploded View of the joint illustrated in Figure-2. v

The furnace I0 shownin Figurel is a conventional construction including a cast metal outlet flue or collar II formed integrally with the combustion chamber, not shown. A sheet metal stove pipe or exhaust pipel2, adapted to be connected to a chimney in a conventional manner, is shown secured to the cast metal collar I I.

The cast metal collar II is formed with a radial face I3 at its outer end and has an axially extending flange I4 at the inner periphery of said radial face I3. The radial face I3 is provided with an axially extending annular groove I5 adjacent the base of the axial flange I4.

The sheet metal cylinder I2 is of an internal diameter only sufficiently greater than the external diameter of the axial flange I4 to permit the sheet metal cylinder to be mounted on the flange as shown in Figure 2. The cylinder I2 is provided with a relatively short radially extending flange I6 at the end thereof. The radial extent of flange I6 is less than the radial extent of groove I5 so that the flange is located within the radial confines of the groove. 25 I A cast metal sleeve ll of an internal diameter substantially the same as the external diameter of the sheet metal cylinder I2 is mounted upon the cylinder I2. Cast metal sleeve H has a radial flange I8 at the end thereof which is of a radial extent locating its periphery in alignment with the outer periphery of the radial face I3 of cast metal cylinder I I.

A plurality of threaded recesses I9 are provided in the radial face I3 of the cast metal cylinder I9 adjacent the outer periphery thereof. Flange I8 of cast metal sleeve I1 is provided with a corresponding number of openings 29 adapted to be arranged in alignment with the openings I9. Cap screws 2| are provided for each of the cooperat- 40 ing openings I9 and 20 by means of which the radial flange I8 of cast metal sleeve 11 is connected to the radial face I3 of the cast metal cylinder with the radial flange I6 of the sheet metal cylinder I2 positioned therebetween. Preferably the radial face I3 and the radial flange I8 are formed with corresponding boss portions at their peripheries in which the openings I 9 and 20, respectively, are located, as shown in Figure 1.

In assembling the parts thus far described, the annular groove I5 of cast metal cylinder II is partially filled with .adhesive material, such as furnace cement 22, or the like. A fibrous ring or rope 23, such as asbestos or the like, is then placed in the groove I5 on top of the cement 22. There- 55 very tight joint is formed between the cast metal cylinder II and the sheet metal cylinder l2. It will be noted that the cap screws 2| are located radially outwardly of the periphery of the flange H5 at the end of the cylinder l2, so that the sheet metal cylinder I2 is secured to the cast metal cylinder II solely by reason of the sheet metal flange l6 being pressed between the packing material contained in groove l5 and the radial flange l8 of cast metal sleeve l'l.

While the present invention has been herein shown and described as embodied in a. joint for connecting a sheet metal stove pipe to the cast metal collar of a combustion chamber for a furnace, it will be readily understood that it may be embodied in various other forms of devices without departing from the spirit or scope of the appended claim.

I claim: A joint construction comprising: a tubular member having a radial flange at one end thereof, an axially extending flange at the inner periphery of said radial flange, and an axially extending annular groove formed in the radial flange adjacent the base of said radial flange; a second tubular member having an end portion encircling the axial flange of the first member; said second member having a radial flange of less radial extent than said annular groove and located wholly within the radial confines of said annular groove; a sleeve surrounding said second tubular member and having a radial flange contacting the radial flange of the second tubular member and the radial flange of the first tubular member; the groove in the first tubular member being filled with flexible sealing material; and means for securing the radial flange of the sleeve to the radial flange of the first mentioned tubular member radially outwardly of. the periphery of the flange at the end of the second tubular member, the construction and arrangement being such that when the sleeve is secured to said radial flange of the first-mentioned tubular member the flange of the second tubular member will be embedded in said sealing material.

' MARTIN DE LIN. 

